#include <pthread.h>
class Mutex
{
public:
    Mutex(pthread_mutex_t *lock) : lock_(lock) {}
    void Lock()
    {
        pthread_mutex_lock(lock_);
    }
    void Unlock()
    {
        pthread_mutex_unlock(lock_);
    }
    ~Mutex() {}

private:
    pthread_mutex_t *lock_;
};
class LockGuard
{
public:
    LockGuard(pthread_mutex_t *lock) : mutex(lock)
    {
        mutex.Lock();
    }
    ~LockGuard()
    {
        mutex.Unlock();
    }

private:
    Mutex mutex;
};